linux/fs/xfs/xfs_itable.c
Dave Chinner 5132ba8f2b xfs: don't cache inodes read through bulkstat
When we read inodes via bulkstat, we generally only read them once
and then throw them away - they never get used again. If we retain
them in cache, then it simply causes the working set of inodes and
other cached items to be reclaimed just so the inode cache can grow.

Avoid this problem by marking inodes read by bulkstat not to be
cached and check this flag in .drop_inode to determine whether the
inode should be added to the VFS LRU or not. If the inode lookup
hits an already cached inode, then don't set the flag. If the inode
lookup hits an inode marked with no cache flag, remove the flag and
allow it to be cached once the current reference goes away.

Inodes marked as not cached will get cleaned up by the background
inode reclaim or via memory pressure, so they will still generate
some short term cache pressure. They will, however, be reclaimed
much sooner and in preference to cache hot inodes.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-26 17:19:08 -05:00

729 lines
20 KiB
C

/*
* Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_ialloc.h"
#include "xfs_itable.h"
#include "xfs_error.h"
#include "xfs_btree.h"
#include "xfs_trace.h"
STATIC int
xfs_internal_inum(
xfs_mount_t *mp,
xfs_ino_t ino)
{
return (ino == mp->m_sb.sb_rbmino || ino == mp->m_sb.sb_rsumino ||
(xfs_sb_version_hasquota(&mp->m_sb) &&
(ino == mp->m_sb.sb_uquotino || ino == mp->m_sb.sb_gquotino)));
}
/*
* Return stat information for one inode.
* Return 0 if ok, else errno.
*/
int
xfs_bulkstat_one_int(
struct xfs_mount *mp, /* mount point for filesystem */
xfs_ino_t ino, /* inode to get data for */
void __user *buffer, /* buffer to place output in */
int ubsize, /* size of buffer */
bulkstat_one_fmt_pf formatter, /* formatter, copy to user */
int *ubused, /* bytes used by me */
int *stat) /* BULKSTAT_RV_... */
{
struct xfs_icdinode *dic; /* dinode core info pointer */
struct xfs_inode *ip; /* incore inode pointer */
struct xfs_bstat *buf; /* return buffer */
int error = 0; /* error value */
*stat = BULKSTAT_RV_NOTHING;
if (!buffer || xfs_internal_inum(mp, ino))
return XFS_ERROR(EINVAL);
buf = kmem_alloc(sizeof(*buf), KM_SLEEP | KM_MAYFAIL);
if (!buf)
return XFS_ERROR(ENOMEM);
error = xfs_iget(mp, NULL, ino,
(XFS_IGET_DONTCACHE | XFS_IGET_UNTRUSTED),
XFS_ILOCK_SHARED, &ip);
if (error) {
*stat = BULKSTAT_RV_NOTHING;
goto out_free;
}
ASSERT(ip != NULL);
ASSERT(ip->i_imap.im_blkno != 0);
dic = &ip->i_d;
/* xfs_iget returns the following without needing
* further change.
*/
buf->bs_nlink = dic->di_nlink;
buf->bs_projid_lo = dic->di_projid_lo;
buf->bs_projid_hi = dic->di_projid_hi;
buf->bs_ino = ino;
buf->bs_mode = dic->di_mode;
buf->bs_uid = dic->di_uid;
buf->bs_gid = dic->di_gid;
buf->bs_size = dic->di_size;
buf->bs_atime.tv_sec = dic->di_atime.t_sec;
buf->bs_atime.tv_nsec = dic->di_atime.t_nsec;
buf->bs_mtime.tv_sec = dic->di_mtime.t_sec;
buf->bs_mtime.tv_nsec = dic->di_mtime.t_nsec;
buf->bs_ctime.tv_sec = dic->di_ctime.t_sec;
buf->bs_ctime.tv_nsec = dic->di_ctime.t_nsec;
buf->bs_xflags = xfs_ip2xflags(ip);
buf->bs_extsize = dic->di_extsize << mp->m_sb.sb_blocklog;
buf->bs_extents = dic->di_nextents;
buf->bs_gen = dic->di_gen;
memset(buf->bs_pad, 0, sizeof(buf->bs_pad));
buf->bs_dmevmask = dic->di_dmevmask;
buf->bs_dmstate = dic->di_dmstate;
buf->bs_aextents = dic->di_anextents;
buf->bs_forkoff = XFS_IFORK_BOFF(ip);
switch (dic->di_format) {
case XFS_DINODE_FMT_DEV:
buf->bs_rdev = ip->i_df.if_u2.if_rdev;
buf->bs_blksize = BLKDEV_IOSIZE;
buf->bs_blocks = 0;
break;
case XFS_DINODE_FMT_LOCAL:
case XFS_DINODE_FMT_UUID:
buf->bs_rdev = 0;
buf->bs_blksize = mp->m_sb.sb_blocksize;
buf->bs_blocks = 0;
break;
case XFS_DINODE_FMT_EXTENTS:
case XFS_DINODE_FMT_BTREE:
buf->bs_rdev = 0;
buf->bs_blksize = mp->m_sb.sb_blocksize;
buf->bs_blocks = dic->di_nblocks + ip->i_delayed_blks;
break;
}
xfs_iunlock(ip, XFS_ILOCK_SHARED);
IRELE(ip);
error = formatter(buffer, ubsize, ubused, buf);
if (!error)
*stat = BULKSTAT_RV_DIDONE;
out_free:
kmem_free(buf);
return error;
}
/* Return 0 on success or positive error */
STATIC int
xfs_bulkstat_one_fmt(
void __user *ubuffer,
int ubsize,
int *ubused,
const xfs_bstat_t *buffer)
{
if (ubsize < sizeof(*buffer))
return XFS_ERROR(ENOMEM);
if (copy_to_user(ubuffer, buffer, sizeof(*buffer)))
return XFS_ERROR(EFAULT);
if (ubused)
*ubused = sizeof(*buffer);
return 0;
}
int
xfs_bulkstat_one(
xfs_mount_t *mp, /* mount point for filesystem */
xfs_ino_t ino, /* inode number to get data for */
void __user *buffer, /* buffer to place output in */
int ubsize, /* size of buffer */
int *ubused, /* bytes used by me */
int *stat) /* BULKSTAT_RV_... */
{
return xfs_bulkstat_one_int(mp, ino, buffer, ubsize,
xfs_bulkstat_one_fmt, ubused, stat);
}
#define XFS_BULKSTAT_UBLEFT(ubleft) ((ubleft) >= statstruct_size)
/*
* Return stat information in bulk (by-inode) for the filesystem.
*/
int /* error status */
xfs_bulkstat(
xfs_mount_t *mp, /* mount point for filesystem */
xfs_ino_t *lastinop, /* last inode returned */
int *ubcountp, /* size of buffer/count returned */
bulkstat_one_pf formatter, /* func that'd fill a single buf */
size_t statstruct_size, /* sizeof struct filling */
char __user *ubuffer, /* buffer with inode stats */
int *done) /* 1 if there are more stats to get */
{
xfs_agblock_t agbno=0;/* allocation group block number */
xfs_buf_t *agbp; /* agi header buffer */
xfs_agi_t *agi; /* agi header data */
xfs_agino_t agino; /* inode # in allocation group */
xfs_agnumber_t agno; /* allocation group number */
int chunkidx; /* current index into inode chunk */
int clustidx; /* current index into inode cluster */
xfs_btree_cur_t *cur; /* btree cursor for ialloc btree */
int end_of_ag; /* set if we've seen the ag end */
int error; /* error code */
int fmterror;/* bulkstat formatter result */
int i; /* loop index */
int icount; /* count of inodes good in irbuf */
size_t irbsize; /* size of irec buffer in bytes */
xfs_ino_t ino; /* inode number (filesystem) */
xfs_inobt_rec_incore_t *irbp; /* current irec buffer pointer */
xfs_inobt_rec_incore_t *irbuf; /* start of irec buffer */
xfs_inobt_rec_incore_t *irbufend; /* end of good irec buffer entries */
xfs_ino_t lastino; /* last inode number returned */
int nbcluster; /* # of blocks in a cluster */
int nicluster; /* # of inodes in a cluster */
int nimask; /* mask for inode clusters */
int nirbuf; /* size of irbuf */
int rval; /* return value error code */
int tmp; /* result value from btree calls */
int ubcount; /* size of user's buffer */
int ubleft; /* bytes left in user's buffer */
char __user *ubufp; /* pointer into user's buffer */
int ubelem; /* spaces used in user's buffer */
int ubused; /* bytes used by formatter */
xfs_buf_t *bp; /* ptr to on-disk inode cluster buf */
/*
* Get the last inode value, see if there's nothing to do.
*/
ino = (xfs_ino_t)*lastinop;
lastino = ino;
agno = XFS_INO_TO_AGNO(mp, ino);
agino = XFS_INO_TO_AGINO(mp, ino);
if (agno >= mp->m_sb.sb_agcount ||
ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
*done = 1;
*ubcountp = 0;
return 0;
}
if (!ubcountp || *ubcountp <= 0) {
return EINVAL;
}
ubcount = *ubcountp; /* statstruct's */
ubleft = ubcount * statstruct_size; /* bytes */
*ubcountp = ubelem = 0;
*done = 0;
fmterror = 0;
ubufp = ubuffer;
nicluster = mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp) ?
mp->m_sb.sb_inopblock :
(XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog);
nimask = ~(nicluster - 1);
nbcluster = nicluster >> mp->m_sb.sb_inopblog;
irbuf = kmem_zalloc_greedy(&irbsize, PAGE_SIZE, PAGE_SIZE * 4);
if (!irbuf)
return ENOMEM;
nirbuf = irbsize / sizeof(*irbuf);
/*
* Loop over the allocation groups, starting from the last
* inode returned; 0 means start of the allocation group.
*/
rval = 0;
while (XFS_BULKSTAT_UBLEFT(ubleft) && agno < mp->m_sb.sb_agcount) {
cond_resched();
bp = NULL;
error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
if (error) {
/*
* Skip this allocation group and go to the next one.
*/
agno++;
agino = 0;
continue;
}
agi = XFS_BUF_TO_AGI(agbp);
/*
* Allocate and initialize a btree cursor for ialloc btree.
*/
cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno);
irbp = irbuf;
irbufend = irbuf + nirbuf;
end_of_ag = 0;
/*
* If we're returning in the middle of an allocation group,
* we need to get the remainder of the chunk we're in.
*/
if (agino > 0) {
xfs_inobt_rec_incore_t r;
/*
* Lookup the inode chunk that this inode lives in.
*/
error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE,
&tmp);
if (!error && /* no I/O error */
tmp && /* lookup succeeded */
/* got the record, should always work */
!(error = xfs_inobt_get_rec(cur, &r, &i)) &&
i == 1 &&
/* this is the right chunk */
agino < r.ir_startino + XFS_INODES_PER_CHUNK &&
/* lastino was not last in chunk */
(chunkidx = agino - r.ir_startino + 1) <
XFS_INODES_PER_CHUNK &&
/* there are some left allocated */
xfs_inobt_maskn(chunkidx,
XFS_INODES_PER_CHUNK - chunkidx) &
~r.ir_free) {
/*
* Grab the chunk record. Mark all the
* uninteresting inodes (because they're
* before our start point) free.
*/
for (i = 0; i < chunkidx; i++) {
if (XFS_INOBT_MASK(i) & ~r.ir_free)
r.ir_freecount++;
}
r.ir_free |= xfs_inobt_maskn(0, chunkidx);
irbp->ir_startino = r.ir_startino;
irbp->ir_freecount = r.ir_freecount;
irbp->ir_free = r.ir_free;
irbp++;
agino = r.ir_startino + XFS_INODES_PER_CHUNK;
icount = XFS_INODES_PER_CHUNK - r.ir_freecount;
} else {
/*
* If any of those tests failed, bump the
* inode number (just in case).
*/
agino++;
icount = 0;
}
/*
* In any case, increment to the next record.
*/
if (!error)
error = xfs_btree_increment(cur, 0, &tmp);
} else {
/*
* Start of ag. Lookup the first inode chunk.
*/
error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &tmp);
icount = 0;
}
/*
* Loop through inode btree records in this ag,
* until we run out of inodes or space in the buffer.
*/
while (irbp < irbufend && icount < ubcount) {
xfs_inobt_rec_incore_t r;
/*
* Loop as long as we're unable to read the
* inode btree.
*/
while (error) {
agino += XFS_INODES_PER_CHUNK;
if (XFS_AGINO_TO_AGBNO(mp, agino) >=
be32_to_cpu(agi->agi_length))
break;
error = xfs_inobt_lookup(cur, agino,
XFS_LOOKUP_GE, &tmp);
cond_resched();
}
/*
* If ran off the end of the ag either with an error,
* or the normal way, set end and stop collecting.
*/
if (error) {
end_of_ag = 1;
break;
}
error = xfs_inobt_get_rec(cur, &r, &i);
if (error || i == 0) {
end_of_ag = 1;
break;
}
/*
* If this chunk has any allocated inodes, save it.
* Also start read-ahead now for this chunk.
*/
if (r.ir_freecount < XFS_INODES_PER_CHUNK) {
/*
* Loop over all clusters in the next chunk.
* Do a readahead if there are any allocated
* inodes in that cluster.
*/
agbno = XFS_AGINO_TO_AGBNO(mp, r.ir_startino);
for (chunkidx = 0;
chunkidx < XFS_INODES_PER_CHUNK;
chunkidx += nicluster,
agbno += nbcluster) {
if (xfs_inobt_maskn(chunkidx, nicluster)
& ~r.ir_free)
xfs_btree_reada_bufs(mp, agno,
agbno, nbcluster);
}
irbp->ir_startino = r.ir_startino;
irbp->ir_freecount = r.ir_freecount;
irbp->ir_free = r.ir_free;
irbp++;
icount += XFS_INODES_PER_CHUNK - r.ir_freecount;
}
/*
* Set agino to after this chunk and bump the cursor.
*/
agino = r.ir_startino + XFS_INODES_PER_CHUNK;
error = xfs_btree_increment(cur, 0, &tmp);
cond_resched();
}
/*
* Drop the btree buffers and the agi buffer.
* We can't hold any of the locks these represent
* when calling iget.
*/
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
xfs_buf_relse(agbp);
/*
* Now format all the good inodes into the user's buffer.
*/
irbufend = irbp;
for (irbp = irbuf;
irbp < irbufend && XFS_BULKSTAT_UBLEFT(ubleft); irbp++) {
/*
* Now process this chunk of inodes.
*/
for (agino = irbp->ir_startino, chunkidx = clustidx = 0;
XFS_BULKSTAT_UBLEFT(ubleft) &&
irbp->ir_freecount < XFS_INODES_PER_CHUNK;
chunkidx++, clustidx++, agino++) {
ASSERT(chunkidx < XFS_INODES_PER_CHUNK);
/*
* Recompute agbno if this is the
* first inode of the cluster.
*
* Careful with clustidx. There can be
* multiple clusters per chunk, a single
* cluster per chunk or a cluster that has
* inodes represented from several different
* chunks (if blocksize is large).
*
* Because of this, the starting clustidx is
* initialized to zero in this loop but must
* later be reset after reading in the cluster
* buffer.
*/
if ((chunkidx & (nicluster - 1)) == 0) {
agbno = XFS_AGINO_TO_AGBNO(mp,
irbp->ir_startino) +
((chunkidx & nimask) >>
mp->m_sb.sb_inopblog);
}
ino = XFS_AGINO_TO_INO(mp, agno, agino);
/*
* Skip if this inode is free.
*/
if (XFS_INOBT_MASK(chunkidx) & irbp->ir_free) {
lastino = ino;
continue;
}
/*
* Count used inodes as free so we can tell
* when the chunk is used up.
*/
irbp->ir_freecount++;
/*
* Get the inode and fill in a single buffer.
*/
ubused = statstruct_size;
error = formatter(mp, ino, ubufp, ubleft,
&ubused, &fmterror);
if (fmterror == BULKSTAT_RV_NOTHING) {
if (error && error != ENOENT &&
error != EINVAL) {
ubleft = 0;
rval = error;
break;
}
lastino = ino;
continue;
}
if (fmterror == BULKSTAT_RV_GIVEUP) {
ubleft = 0;
ASSERT(error);
rval = error;
break;
}
if (ubufp)
ubufp += ubused;
ubleft -= ubused;
ubelem++;
lastino = ino;
}
cond_resched();
}
if (bp)
xfs_buf_relse(bp);
/*
* Set up for the next loop iteration.
*/
if (XFS_BULKSTAT_UBLEFT(ubleft)) {
if (end_of_ag) {
agno++;
agino = 0;
} else
agino = XFS_INO_TO_AGINO(mp, lastino);
} else
break;
}
/*
* Done, we're either out of filesystem or space to put the data.
*/
kmem_free_large(irbuf);
*ubcountp = ubelem;
/*
* Found some inodes, return them now and return the error next time.
*/
if (ubelem)
rval = 0;
if (agno >= mp->m_sb.sb_agcount) {
/*
* If we ran out of filesystem, mark lastino as off
* the end of the filesystem, so the next call
* will return immediately.
*/
*lastinop = (xfs_ino_t)XFS_AGINO_TO_INO(mp, agno, 0);
*done = 1;
} else
*lastinop = (xfs_ino_t)lastino;
return rval;
}
/*
* Return stat information in bulk (by-inode) for the filesystem.
* Special case for non-sequential one inode bulkstat.
*/
int /* error status */
xfs_bulkstat_single(
xfs_mount_t *mp, /* mount point for filesystem */
xfs_ino_t *lastinop, /* inode to return */
char __user *buffer, /* buffer with inode stats */
int *done) /* 1 if there are more stats to get */
{
int count; /* count value for bulkstat call */
int error; /* return value */
xfs_ino_t ino; /* filesystem inode number */
int res; /* result from bs1 */
/*
* note that requesting valid inode numbers which are not allocated
* to inodes will most likely cause xfs_itobp to generate warning
* messages about bad magic numbers. This is ok. The fact that
* the inode isn't actually an inode is handled by the
* error check below. Done this way to make the usual case faster
* at the expense of the error case.
*/
ino = (xfs_ino_t)*lastinop;
error = xfs_bulkstat_one(mp, ino, buffer, sizeof(xfs_bstat_t), 0, &res);
if (error) {
/*
* Special case way failed, do it the "long" way
* to see if that works.
*/
(*lastinop)--;
count = 1;
if (xfs_bulkstat(mp, lastinop, &count, xfs_bulkstat_one,
sizeof(xfs_bstat_t), buffer, done))
return error;
if (count == 0 || (xfs_ino_t)*lastinop != ino)
return error == EFSCORRUPTED ?
XFS_ERROR(EINVAL) : error;
else
return 0;
}
*done = 0;
return 0;
}
int
xfs_inumbers_fmt(
void __user *ubuffer, /* buffer to write to */
const xfs_inogrp_t *buffer, /* buffer to read from */
long count, /* # of elements to read */
long *written) /* # of bytes written */
{
if (copy_to_user(ubuffer, buffer, count * sizeof(*buffer)))
return -EFAULT;
*written = count * sizeof(*buffer);
return 0;
}
/*
* Return inode number table for the filesystem.
*/
int /* error status */
xfs_inumbers(
xfs_mount_t *mp, /* mount point for filesystem */
xfs_ino_t *lastino, /* last inode returned */
int *count, /* size of buffer/count returned */
void __user *ubuffer,/* buffer with inode descriptions */
inumbers_fmt_pf formatter)
{
xfs_buf_t *agbp;
xfs_agino_t agino;
xfs_agnumber_t agno;
int bcount;
xfs_inogrp_t *buffer;
int bufidx;
xfs_btree_cur_t *cur;
int error;
xfs_inobt_rec_incore_t r;
int i;
xfs_ino_t ino;
int left;
int tmp;
ino = (xfs_ino_t)*lastino;
agno = XFS_INO_TO_AGNO(mp, ino);
agino = XFS_INO_TO_AGINO(mp, ino);
left = *count;
*count = 0;
bcount = MIN(left, (int)(PAGE_SIZE / sizeof(*buffer)));
buffer = kmem_alloc(bcount * sizeof(*buffer), KM_SLEEP);
error = bufidx = 0;
cur = NULL;
agbp = NULL;
while (left > 0 && agno < mp->m_sb.sb_agcount) {
if (agbp == NULL) {
error = xfs_ialloc_read_agi(mp, NULL, agno, &agbp);
if (error) {
/*
* If we can't read the AGI of this ag,
* then just skip to the next one.
*/
ASSERT(cur == NULL);
agbp = NULL;
agno++;
agino = 0;
continue;
}
cur = xfs_inobt_init_cursor(mp, NULL, agbp, agno);
error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_GE,
&tmp);
if (error) {
xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
cur = NULL;
xfs_buf_relse(agbp);
agbp = NULL;
/*
* Move up the last inode in the current
* chunk. The lookup_ge will always get
* us the first inode in the next chunk.
*/
agino += XFS_INODES_PER_CHUNK - 1;
continue;
}
}
error = xfs_inobt_get_rec(cur, &r, &i);
if (error || i == 0) {
xfs_buf_relse(agbp);
agbp = NULL;
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
cur = NULL;
agno++;
agino = 0;
continue;
}
agino = r.ir_startino + XFS_INODES_PER_CHUNK - 1;
buffer[bufidx].xi_startino =
XFS_AGINO_TO_INO(mp, agno, r.ir_startino);
buffer[bufidx].xi_alloccount =
XFS_INODES_PER_CHUNK - r.ir_freecount;
buffer[bufidx].xi_allocmask = ~r.ir_free;
bufidx++;
left--;
if (bufidx == bcount) {
long written;
if (formatter(ubuffer, buffer, bufidx, &written)) {
error = XFS_ERROR(EFAULT);
break;
}
ubuffer += written;
*count += bufidx;
bufidx = 0;
}
if (left) {
error = xfs_btree_increment(cur, 0, &tmp);
if (error) {
xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
cur = NULL;
xfs_buf_relse(agbp);
agbp = NULL;
/*
* The agino value has already been bumped.
* Just try to skip up to it.
*/
agino += XFS_INODES_PER_CHUNK;
continue;
}
}
}
if (!error) {
if (bufidx) {
long written;
if (formatter(ubuffer, buffer, bufidx, &written))
error = XFS_ERROR(EFAULT);
else
*count += bufidx;
}
*lastino = XFS_AGINO_TO_INO(mp, agno, agino);
}
kmem_free(buffer);
if (cur)
xfs_btree_del_cursor(cur, (error ? XFS_BTREE_ERROR :
XFS_BTREE_NOERROR));
if (agbp)
xfs_buf_relse(agbp);
return error;
}